Hydraulic drive for motor vehicles



1953 J. T. ANTLE, JR

HYDRAULIC DRIVE FOR MOTOR VEHICLES 2 SHEETS-SHEET l Filed Feb. 9, 1949 l li y gvwcm/to'o. JOHN T. ANTLE, JR.

Jan. 20, 1953 J. T. ANTLE, JR 2,525,001

HYDRAULIC DRIVE FOR MOTOR VEHICLES Filed Feb. 9, 1949 2 SHEETS-SHEET 2 I -JL Qvwwvfm JOHN T. ANTLE. JR.

attorneys.

Patented Jan. 20, 1953 v.

HYDRAULIC DRIVE FOR MOTOR VEHICLES John T. Antle, Jr., Louisville, Ky., assignor of onehalf to Virginia Devinney, Washington, D. 0.

Application February 9, 1949, Serial No. 75,405

2 Claims. 1

This invention relates to a hydraulic drive for motor vehicles, and more particularly to a hydraulic drive of the type including an engine driven pump, a hydraulic fluid pressure tank, a hydraulic fluid reservoir, hydraulic motors connected mechanically with the wheels, liquid con- :duits leading to and from the several units, and

control mechanisms.

It is an object of the invention to provide a "drive for motor vehicles which eliminates the necessity of transmission gears and gear shifting. It is another object to provide a drive'which smooth and noiseless in operation.

' It is a further object to provide a drive permitting the independent spring suspension of the rear'wheels with a resulting improvement 'in riding comfort.

It is a further object to provide a drive which,

"though relatively trouble-free, may be easily and conveniently repaired.

It a further object to provide a hydraulic drive operated by controls in the manner now generally used, that is through the medium of an accelerator pedal and the equivalent of a steeringpost-supported gear shift lever.

Other objects will be apparent to those skilled in the art from the following description taken with the appended drawings wherein:

Figure 1 is a top plan view of a motor vehicle,

with the body removed, provided with a preferred form of the present invention;

"Figure 2 is a side elevational view of the same;

and

Figure 3 is a top plan view of a motor vehicle, with the body removed, provided with another form of the invention.

Referring now in greater detail to Figures 1 and 2, a conventional chassis I is provided with rear wheels ll, front wheels l2, bumpers -I3,

power plant I4, steering post l5 and steering wheel I6. The power shaft ,ll of the power plant. I4 is directly connected to, and operative Fluid is forced from pressure tank 30 through conduits 31, valves 32, conduits 36 to forward-reverse valves 31.

flexible nozzle conduits 39 to the hydraulic fluid motors 40. The motors 40 are of conventional design, each having a housing 4! rigidly secured to the chassis I0 of the vehicle. Each housing When the vehicle I The valves 31 are selectively operated to direct the fluid either through. flexible nozzle conduits 38 or through 4| has rotatably mounted therein a vaned rotor M which is directly connected to the axles 42 of rear wheels II. Each fluid motor 40 is operative to drive its corresponding wheel ll independently of the other motor 40 and other wheel II. The nozzle conduits 38 are so disposed as to direct fluid against the vanes of the rotor below the axle 42, thereby rotating the wheels H in such a way as to impart forward motion to the vehicle. The nozzle conduits 39- on the other hand are operative to direct fluid against the vanes on the rotor above the axle and thereby cause a rearward movement of the vehicle.

It is apparent that the valves 31 are operative to control the circulation of fluid through the motors 4D in two different directions, namely, into the motors 40 through nozzle conduits 39 and out of the motor through conduits 38, or, alternatively, to the motors through nozzle conduits 38 and from the motors through nozzle conduits 39. Under either condition, the fluid returning to valves 31 is directed through return conduits 45 to a storage reservoir 50. The hydraulic pump 20 draws fluid from the reservoir 50 through a conduit 5|. The path of circulation is thus completed and the fluid is allowed to continuously circulate about the above-described circuit.

In order to providefor a neutral condition when the engine is running and the vehicle is stationary, I provide a by-pass circuit. In this circuit the fluid is forced from the pump .20

through the conduit 2|, by-pass valve 22, a bypass conduit 52, into storage reservoir 50 and return conduit 5! back to the pump 20. The

by-pass valve 22 therefore has two positions/one for driving the vehicle either in the forward or reverse direction, and another for by-passing the hydraulic fluid when the vehicle is stationary.

I provide manually operated mechanism for controlling the fluid in the system which comreverse position to provide for corresponding movements of the vehicle. The hand lever will normally be left in the forward position 3 and be moved to the reverse position only when the vehicle is to be driven rearwardly.

I also provide a foot pedal 10 corresponding to the accelerator pedal of a conventional motor vehicle. The foot pedal 10 is pivotally mounted on the floor board of the vehicle at H. Movement of the pedal 10 is transmitted through a link 12 and an accelerator rod [3 to the carburetor 14 of the power plant I4. Movement of pedal 10 simultaneously acts through the link 12 on a connecting mechanism 15, the other end of the mechanism being connected to a bell crank 16. An actuating rod 11 connects the bell crank T6 with the on-oif valves 32. Movement of pedal 10 is also simultaneously operative to move a linkage rod 18 which is connected on the other end to an actuating arm 19 of the by-pass valve 22. It is therefore apparent that the foot pedal ID is so connected as to control three units, namely the carburetor 14, the on-off valves 32 and the 'bY-Dass valve 22. The mechanical linkages are so constructed and proportioned as to provide for the proper relative simultaneous movements of the three mentioned units. When the pedal 10 is depressed, the power unit I4 is accelerated; the on-ofi valves 32 are opened so as to permit the flow of hydraulic fluid from the pressure tank 3|] to the fluid motors 46; and, at the same time, the by-pass valve 22 is moved from its neutral position to permit the flow of fluid from the pump 20 through conduit 21 to the pressure tank 36.

It is apparent that I have provided a hydraulic drive for a motor vehicle which is easy to operate, has control means actuated by levers which correspond to those commonly employed in motor vehicles, and which is smooth and automatic in operation. The manipulation of the vehicle is remarkably easy. In use the engine is started and if it is desired to move the vehicle forward (the hand lever 60 being normally left in the forward position) the foot pedal I is merely depressed. When the pedal is released, the power unit 14 is automatically decelerated and the valves 32 and 22 are returned to their oil and neutral positions, respectively. It is obvious that the disadvantages and annoyances attendant the manipulation of the motor vehicle incoporating gear shift means are avoided.

Referring to Figure 3, wherein I show a modifled form of the invention, the individual fluid motors 40 connected to corresponding wheels II are replaced by a single hydraulic fluid motor 80. In this form of the invention a motor vehicle, having a conventional rear axle 8i and a differential assembly 82, is employed. The rotor 83 of the hydraulic motor 80 is rigidly secured to the pinion shaft of the difierential 82. The remaining parts and the operation of this embodiment are the same as those previously described in connection with Figures 1 and 2. No diflerential is needed in the first-described form because the fluid motors 40 are independent of each other and are each connectedto a different one of the rear wheels II. By this construction the rear wheels are allowed to rotate at difierent speeds when the vehicle is going around a curve. The form of the invention shown in Figure 3 has a conventional difierential 82 for this purpose.

In the form of invention shown in Figures 1 and 2 the rear wheels H of the vehicle may be individually suspended by springs 84. Independent vertical movement of the wheels II is per- .mitted by reason of said spring suspension and 4 the flexibility of conduits 38 and 39. By this construction both the front and rear wheels are spring mounted, resulting in improved riding comfort and less wear and tear on the vehicle.

While I have shown and described two forms of my invention, it is to be understood that I am not to be limited thereto and that many changes could be made without departing from the scope of the claims hereto appended.

What I claim is:

1. A hydraulic drive for motor vehicles comprising a hydraulic pump and power unit in operative connection, a pressure tank receptive to fluid from the pump, an individual hydraulic motor for each driven wheel, a fluid reservoir, conduits for conveying the fluid through a circuit from the pump to the pressure tank, to the hydraulic motors, to the reservoir and back to the pump, a bypass conduit for conveying fluid from the pump to said reservoir and back to the pump, on-off valves in the conduits between the pressure tank and the hydraulic motors, a by-pass valve in-the by-pass conduit, means operative to simultaneously accelerate the power unit, close the by-pass valve and open the one-ofi valve, forward-reverse valves in the conduits between the pressure tank and the hydraulic motors, said forward-reverse valves being disposed between the on-ofi valves and the motors, and a steering-post-mounted lever and linkages therefor operative to control the forward-reverse valves.

2. A hydraulic drive for differential equipped motor vehicles comprising a hydraulic pump directly connected with the vehicle, motor, a pressure tank receptive to fluid from the pump, a hydraulic motor connected to the rear wheels of the vehicle through the differential assembly, a fluid reservoir, conduits for conveying the fluid through a circuit from the pump to the pressure tank, to the hydraulic motor, to the reservoir and back to the pump, a by-pass conduit for conveying fluid from the pump t the reservoir and back to the pump, on-ofi valves in the conduits between the pressure tank and the hydraulic motor, a by-pass valve in the by-pass conduit, foot pedal means operative when depressed to simultaneously accelerate the vehicle motor, close the by-pass valve and open the on-ofi valve, forwardreverse valves in the conduits between the pressure tank and the hydraulic motor, said forwardreverse valves being disposed between the .on-ofi valves and the motor, and a steering-postmounted lever and linkages therefor operative to control the forward-reverse valves.

JOHN T. AN'I'LE, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,138,667 Kitchen May 11, 1915 1,347,279 Kraus July 20, 1920 2,279,008 Nathan Apr. 7, 1942 2,393,324 Joy Jan. 22, 1946 2,516,662 Vickers et al. July 25, 1950 FOREIGN PATENTS Number Country Date 364,942 France June 13, 1906 569,567 France Jan. 8, 1924 

